MgCl2负载型Ziegler-Natta钛系催化剂仍是目前主要的工业聚乙烯催化剂之一，配位聚合机理不明是阻碍本领域进一步发展的关键。本项目前期工作表明，新型硅/镁复合载体型Ziegler-Natta钛系聚乙烯催化剂（(SiO2/MgO/MgCl2)·TiClx）制备工艺简单，无需使用水氧敏感的镁源，且表现出优良的聚合性能，具有重要的工业应用前景。本项目拟采用实验和计算机分子模拟相结合的方法对该新型聚乙烯催化剂结构性能、聚合机理等进行深入系统研究。实验将采用聚合动力学结合原位红外、EXAFS以及微量吸附量热等技术，计算模拟将采用密度泛函理论（DFT）方法，协同考察MgCl2载体的原位形成机制、助催化剂在活性中心形成过程中的作用机理、不同金属或非金属元素载体改性对催化剂催化乙烯聚合及其与α-烯烃共聚性能的影响规律、第二种金属钒活性中心的引入及其与钛中心的协同作用等。

MgCl2 supported Ziegler-Natta catalyst is still one of the main industrial polyethylene catalysts, while the unknown mechanism of coordination polymerization hindered the further development of this field. Our preliminary work about the novel Ziegler-Natta Ti-based polyethylene catalyst ((SiO2/MgO/MgCl2)·TiClx) over Si/Mg composite support indicated its simple preparation process without using any moisture- or air-sensitive magnesium source, and it exhibited good polymerization performance, which showed great potential for industrial applications. This project intends to combine experiments with computational molecular modeling methods to investigate the catalyst structural-property relationship and polymerization mechanism. For experiments, polymerization kinetics will be combined with In-Situ IR, EXAFS and microcalorimetric adsorption techniques. Density functional theory (DFT) will be applied for molecular modeling. The in situ formation mechanism of MgCl2 support, the role of Al-alkyl cocatalyst during the active site formation, different metal or non-metal element modification of the support surface on the catalytic polymerization performance and the effects on the ethylene homo-polymerization and copolymerization with α-olefin, the introduction of the second metal vanadium active site and its synergetic effect with the titanium active site will be systematically studied. The results from this work will provide strong theoretical basis for the development of novel and highly efficient catalyst and polyethylene products with high performance.